1. Field of the Invention
This invention relates to acyloxysteroids which are useful as a novel intermediate for use in the preparation of adrenocortical hormones such as hydrocortisone, prednisolone and the like.
2. Description of the Prior Art
Recently, androst-4-ene-3,17-dione and androsta-1,4-diene-3,17-dione have been produced in large quantities and inexpensively from sterols such as cholesterol, sitosterol and the like by the use of microorganisms belonging to the genus Mycobacterium and thus various steroidal drugs such as estrone, testosterone, spironolactone, etc. have been produced from these starting materials.
On the other hand, adrenocortical hormones (corticoids) which occupy a major proportion of the steroidal drugs are still prepared using as an intermediate progesterone from stigmasterol or 16-dehydropregnenolone from diosgenin, or they are prepared from bile acids via a process comprising many steps.
We have made extensive studies to develop a more economical process for preparing corticoids from starting materials including not only the aforementioned androst-4-ene-3,17-dione and androsta-1,4-diene-3,17-dione which have recently been produced in large quantities and inexpensively, but also androsta-4,9.sup.(11) -diene-3,17-dione which has been produced from 9.alpha.-hydroxyandrost-4-ene-3,17-dione which has also recently been produced by a fermentative process. It has now been found that acyloxysteroids which are useful as a starting material in the preparation of corticoids can be obtained from the above-described starting materials.